Electric switch



May 8, 1928. I l v 1,669,283

J. R. cARLsoN ELECTRIC SWITCH Filed NOV. 10, 1922 /NVENTOR ToHQ/vn/Es E'. CHRLSoN /I TTORNEYS Patented May 8, 1928`.

UNITI-:D STATES PATENTl OFFICE.

JOHANNES R. CARLSON, OF HARTFORD, CONNECTICUT, ASSIGNOR `'.lO THE ARROW'4 Y ELECTRIC COMPANY, or HARTFORD,

NECTICUT.

CONNECTICUT, a' CORPORATION or CoN- ELECTRIC SWITCH.

Application led November 1922. Serial No. I800,13*?.

Myni-nvention relates to electric switches, and particularly to rotary snap switches; The objectof my -invention'is toprovide an improved switch spring mounting on and 5 actuating connection with theswitch spindle.

In time accompanying drawings- -Figf is a broken side elevation otr.A switch to which my invention is apphed 1n one, form;

l Fig. 2 is a perspective of the switch spindle illustrating the switch spring mountlng thereon; Fig. 3) is a vertical section therethrough;

Fig. 4i's a section on the line 4-4, F1g. 3;

' and Fig. 5 is a perspective of one element of t-he mounting.

The present invention is particularly d1- rected to the mounting on the switch spindle- 2" of the torsion spring through which actuating connection .is established .betweenv the spindle and blades `of a rot-ary snap switch. Theconstruction of the spring 1s not of essential'importance, but I have illustrated a.

V springof the character shown in the patent of Benjamin C. Perkins, 1,564,016,f0r which the present mounting vis especlally designed.

The construction of the` escapement meeganism and of the switch blades also for s of lllustration, however, I have shown a switch of the type used for controlllng the circuits of a heater element in an electric ran e. T us the insulating base 6 supports the `rotary switch spindle 7' engaged bylthe operating'handle 8. Switch blades-9 are freely rotatableon the spindle, and an escapement mechanism, generally indicated by the reference l10, is provided, by means of which the blades are temporarily detained during the wind-up .of the driving spring 11 bythe 'rotation of the spindle. The switch mechanism is as usual enclosed by the cover 12 dl with its insulating lining 13. y

The presentinvention relates particularly to the means by which the switch-spring 1s mounted upon and actuated by the spindle.

`For this purpose I provide a cage compris-l ing a. diving plate 14 and anassociated dog plate 1 between which the spring l11 is yconfined. The driving plate 14 is pierced by akey aperture 16,v the y circular portion a of i which is of such diameter that'the plate may 55 be freely passed over the spindle. The slot ortion of my invention. For* the sakeA -duced ends 19 of shouldered dogs 20 upstanding from the plate 15. In assembled position the shoulders 21 oi the dogs 20abut against the adjacent faceA of the plate 14,

while the reduced ends of thelugs 19 project slightly through theS latter `and are spread to rivet the plates together with the *spring 11 confined in the space between the plates.

lOne pr the other of the dogs 2() is spanned and engaged undertension by the offsets 22 and 23 of the circumferentially overlapping ends of Lthe switch spring 11. These offsetV ends 22 and 23 project outwardly beyond the dog 20 suiiiciently to engage also the opposite sides of the cooperating dog 24 of the plate 25 secured to the -switch blade ele- 'ment 9.

It is thus obvious that upon the rotation ofthespindle 7, the switch' spring cage is rotated with .the spindle, and one or the other of the ends 22 and 23 of the spring is carried around therewith by the dog 20, while-the' other spring end is detained by the dog 24 of the switch blade clement until the g escapement mechanism 10 releases the latter and permits the same to rotate under the torsional effort of the spring. V'hen the escapevment mechanism 10 is of such character as to permit the rotation of the spindle in either direction, the operation is the same regardless pf the direction of rotation of the spin-v e The construction presents various features of improvement. Thus inthe finished switch lill the accurate location of the spring with refkup or down on the spindle, with the accompanying danger of possible escape of its ends from the dog 24. The length of the dog 24.

may therefore be reduced without incurring` any danger of failure 1n the switch mecha-l nism. Secondly, should the switch spring become ruptured by any possibility, it is still retained by the cage and there is nodanger that it may escape and bridge the contacts of the switch, thus causing ashort circuit and dangerous conditions on thel line.

From the manufacturing standpoint, the construction is an advantage, since both the plates 14 and 15 may be readily struck from sheet metal and formed to shape, and are thus economical to manufacture. Assembly is facilitated, since the driving plate 14C is readily slipped on the spindle and locked at 17. Moreover, when the spring is placed on the dog plate 15 and its otfset en'ds 22 and 23 engaged under tension with and straddling one of the dogs 20, the spring is automatically retained in position on the plate 15. The latter thus forms an assembly unit which may be readily passed over the spin-4 dle and engaged with the driving plate 14. The plain bearing aperture26 formed axially in the plate 15, notonly centers the latter on the spindle, but also prevents lateral displacement of the plate 14. Its operating drive connection with the spindle is thus assured.

Obviously, there may be more than the two dogs 2() on the plate 15 for holding the parts assembled. It isvnot necessary that the plates 14: and 15 be shaped as discs although. I prefer the latter, since this shape completely contines and supports the spring engaging area adapted to be brought into operative engagement with the spindle by the lateral movement of the plate. with respect thereto,1`neans to ypermanently -lock said plate in spindle-engaging position, a

spring interposed between said means and driving plate, and an offset dog extending into the plane of the spring to engage anl end of the latter and wind the spring on the rotation of the spindle 2. In an electric switch, a rotary switch spindle having a fiat, a switch spring and a spring mounting comprising a pla-te having a key slot engagement with thespindle fiat, a second plate spaced therefrom and accommodating the spring therebetween, means for Securing said platesv together to prevent lateral movement and disengagement of the key slotted plate with respect to the spindle, and a dog associated with one of said plates to engage an end of the spring.

3. A switch spindle having a flatted area, a plat-e slotted for engagement with said spindle Hat by transverse movement ot' the plate with respect to the spindle, a second plate apertured to accommodatev the spindle but restrained against transverse movement with respect thereto,'means uniting said plates, and a coil spring surrounding said spindle between the plates and having an offset end engaged with one of said plates.

4. A switch spindle having a flatted area, a plate slotted for engagement with said spindle fiat by transverse movement of the plate with respect to the spindle, a second plate apertured to accommodate the spindle but restrained against transverse movement -with respect thereto, spacer means uniting said plates, a coil spring arranged on the lspindle between the plates and having its plates apart, the reduced ends of said lugs entering said recesses and being spread to rivet the plates together.

In testimony whereof I have signed my name to this specification.

' JOHANNES n. CARLSON. 

